Hydraulic jack



July 15, 1924. 1 1,501,151

'5. V. THOMPSON HYDRAULI C JACK f Filed dan. 27, 1922 8 a y, l

INI/EN TOR. YLVESTEE 1./7/70/7/:50/1

A TTORNEYS.

SYLVV. THOMPSDN, F DIEGO, CALIFORNIA.'

il RAULIC JACK. V

Application led January 27, 1922. Serial No. 532,182.

, to provide a'jack of this class in which the wearing parts are reduced to a minimum;

third, to provide a jack of this class which requires no springs in connection with its essential o erating valves to keep the same elevational view, portions being closed; ourth, to provide a jack of this class which is efficient and positive in action; fifth, t provide a jack of this class which is novelly constructed; Vand sixth, to

provide a jack of this -class which may be' owered any distance desired and hold the load in such lowered position, and seventh, to provide a jack of this class which is simle, economical and compact in construction, urable, easy to apply and operate, and which will not readily deteriorate or get out of order.

With these and other objects in view as will appear hereinafter my invention consists of certain novel features of construction, combination and arrangement of parts and portions as will be hereinafter described in detail and particularly set forth in the appended claims reference being had to the accompanying drawings and to the characters of reference thereon which form a part of this application in which:

Figure 1. is a longitudinal view through the center line of my jack, taken on the line 1-1 of Fig. 2; Fig. 2 is a plan view thereof, parts being broken away to facilitate the illustration; Fig. 3 is a fragmentary elevational view showing the handle in operative position; Fig. 4 is a sectional view through 4-4 of Fig. 1; and Fig. 5 is a fragmentary broken away to facilitate the illustration of the releasing device.

Like characters ofreference refer to similar parts and ortions throughout the several views of t e drawin Thecasin 1, base 2, p unger 3, jack head 4, pin 5, bus ing 6, bolt 7, spring 8, plug 9, plunger leather 10, disk 11, screw 12, plunger 13, links 14 and 15, operating arm 16,

`lever 17, bushing 18, valve plugs 19, 20 and 21, balls 22, pins 23, finger 24, lever 25, pivot member 26, release rod 27, bushin 28, spring 29, and the combination breatin valves and filling plug 30` constitute the principal parts and portions of my structure. 1 The casing 1 is provided in its up er portion with a ongitudinal bore or cylinder 1 to receive the reciprocating plunger 3. Said casing is provided at its lower. enlarged portion with a circular chamber partly surrounding the lower end of the cylinder member of said casing, said chamber serving as an oil reservoir, or reservoir for the liquid which may be used in the jack. Said lower enlarged portion of the casing is provided with a base 2 screwed therein which base also serves as a cover or seal for the oil reservoir 1*. The plun er .3 is provided at its upper end with a jac head 4, secured thereto by means of a pin 5. The cylinder portion of the casing is provided at its upper end with a bushing .6 screwed therein. Interposed between the lower end of said bushing and a shoulder 1 of the casing is a packing 6a held `or clamped in position by said bushing forming a stuffing box to revent the oil or other liquid used from passmg out of the upper end of the cylinder member of said casing. Said bushing 6 is provided in one side with a hole 6l to receive a bolt 7 which is held -a ainst theplunger by the screw plug 9 am? a spring 8 inter sed between said bolt and said plug. Sa1d bolt is adapted to engage an annular groove 3a atv the lower end of the plunger 3 to prevent said plunger from'being forced out of the upper end of the cylinder member of the casing 1. Said casing is provided at its lower enlarged portion with a bore 1d parallel to the axis of the bore 1, adapted to receive the plun er 13. Said plunger is made leakproo with said casing by a bushing 18 provided near its upper end and secured in'said casing and a packing 18interposed between said bushing and a .shoulder 1 in the lower portion of said casing concentric with the bore 1d. An operating arm 16 is pivotally connected to the upper end of lunger 13 by a pair of spaced links 14. Said operating arm is fulcrumed on the lug 1f, at the lower enlarged portion of said casing by a pair of links 15 pivotally secured to and intermediate said operating arm and said lug. Said operating armis provided with a tapered recess 16 to receive either of the ta ered ends 17 or 17b of the lever 17. Axia y in line with the vplunger 13 and secured in the lower end of the casin is a valve plug 19 provided with an ori ce 19, an enlarged orifice 19b and a valve seat 19, the lower orifice 19 communicating with the oil reservoir 1" of the casin 1, the larger orifice communicating with t e cylinder or bore 1d for the plunger 13. Saidvalve plug is provided with a ball 22 resting on the seat 19 and a in 23 serving as a stop to revent said ba l being drawn up into the c amber of said lunger. A similar valve plu is provi ed to communicate with t e ore 1d of said lunger by means of the port 1g and with tlie cylinder or bore 1 engagin the ump leather 10 secured to the lower en mounted on a lever 25 which is of t e piston 3 by means of the disk 11 and a screw 12. A third valve plug 21 is secured at the lower end of said casing communicating with the cylinder 1 and the oil reservoir l" of said casing. A. finger 24 adapted to enage the ball 22 of said latter valve plug ifting the same 0H its seat is pivotally fulcrumed on a pivot secured on the lower face of said casin A release rod 27 is provided with a slot 2 adapted to engage the other end of said lever 25. Said release rod is reciprocably mounted in the enlarged portion of said casing, its upper end extending therethrough and is provided with a knob 27". A spring 29 is interposed between the busin 28 adapted to make said rod leak proof, an a shoulder formed by the head 27" of said release rod. The combination breathing valves and filling plug is provided at the lower enlarged portion of said'casing communicating with the oil reservoir. Said plug can readily be removed or filling said reservoir and is adapted to permit air to pass in and out of said reservoir to eliminate undue pressure or vacuum formed therein.

It is obvious that when the lever 17 and operating arm 16, fulcrumed through the links 15 on the lug 1t of the casing, are raised the plun er 13 is also raised, drawing in a charge o? oil, or li uid that is used, through the orifice 19 of t e valve plug 19, raising the ball 22 therein from its seat and drawing said charge within the chamber or bore 1d. When the lever 17 is moved downwardly the plunger 13 is also moved downwardly compressing the oil within the said chamber and forcing the same through the port 1B and the orifice of the valve plug 20 raising the ball 22 therein from its seat and discharging the saine within the cylinder 1 underneath the piston 3 forcing the same upwardly. By repeating the operation mentioned the piston 3 may be raised any distancedesired within its limit, that is, until the bolt 7 engages the annular groove 3a on i said piston.

' lt is-further obvious that when a slight force is exerted on the knob 27" of the release rod the spring 29 is compressed swinging the lever 25 about its pivot 26 and raising the finger 24, thereby disenga 'ng the1 ball 22 from its seat within the vigile plug 21 thus discharging the oil or liquid that is used from the cylinder 1" by a force that may be exertedat the u per end of the piston 3 or on the jack head 4: or by the weight of the piston itself. K

Though I have shown and described a particular construction, combination, and arrangement of parts and portions l do not wish to be limited to this particular construction, combination and arrangement but desire to include in the scope of my invention the construction, combination and arrangement substantially as set orth in the ap ended claims.

aving thus described my invention what I claim as new and desire to secure by Letters Patent is: y

1. A hydraulic jack, including a casing, a cylinder portion at the up er end and an enlar ed reservoir base portion at the lower end t ereof, a lunger reciprocably mounted in the cylin er portion thereof, anotheri plunger reciprocably mounted in the lower enlarged end of said casing parallel with said first mentioned plunger, a means for reciprocably operating said first mentioned plunger, a check valve interposed between said reservoir and the chamber of said other plunger for controlling the flow of oil tosaid chamber, a second check valve interposed between said chamber and the cylinder portion of said casing for controlling the flow of liquid thereto, a third check valve interposed between said cylinder'portion of said casing and said reservoir for controlling the discharge of the liquid from said cylinder/ and means for operating said latter valve,

said means consisting of a rod extending through the wall of the enlar ed reservoir base portion of said casing, an a lever pivotally mounted intermediate its ends within said reservoir, its one end being connected with the inwardly extended end of said rod, its other end being adapted to engage the valve member of said last mentioned check valve with the inward shifting of said rod.

2. A hydraulic jack, including a casingfa cylinder portion at the upper end, and a reservoir at the lower end thereor` surrounding the lower end of said cylinder portion, a plunger reciprocably mounted in the cylinder portion of said casing, a jack head secured to the upper extended end of said piston, a bushing secured in the upper end of said cylinder portion, a spring actuated bolt within said bushing engaging said piston and adapted to engage an annular groove portion at the lower end of said piston to prevent withdrawal of the same, another momen a lunger reciprocably mounted within the 'casing and reservoir for controlling the dis? ower end of said casing parallel with said charge of liquid from said cylinder and l0 first mentioned plunger, a means for recipromeans for operating said latter valve. cably operating said other plunger, a check In testimony whereof, I have hereunto set e valve interposed between `said reservoir and my hand at San Diego, California this;l 20th the cylinder portion of said casing controlday of January, 1922. ling the flow of liquidthereto, a check valve interposed between said inner portion of said SYLVESTER V. THOMPSON. 

